Evaporator for refrigerating plants



April 1930- E. FREUVNDLICH 1,753,856

EVAPORATOR FOR REFRIGERATING PLANTS Filed Sept. 7, 1928 l N VEN TOR.

l azwzzfa 1 ATTORNEY.

ERICK FREUNDLICH, OE DUSSELDORF-OBERKASSEL, GERMANY EvAroRA'roR FOR 'REFRIGERATING PLANTS Application filed September 7, 1928, Serial No. 304,500, and in Germany March 17, 1928.

My invention has reference to refrigeration and more particularly to evaporators for refrigerating machines. The principal desideratum of such evaporators is good heat transmission, whichmainly depends on the conditions on either side of the evaporator both as to the heat transmitting and the heat absorbing material. The object of the pres ent invention is to produce an evaporator forv requiring but small space, of cheap manufacture and easy operation and maintenance.

Since the transmission of heat of a liquid to the wall of a pipe is a multiple of that of a gas, it is important to flood the pipe, or, in

. other words, to moisten all portions of the pipe with the liquid and to remove the vapor bubbles as quickly as possible. Also, the flow of the vapors while being discharged must not meet with any great resistance, because otherwise the work of compression would be uselessly increased thereby. Therefore, it

is advisable to arrange the pipes of the evaporator in large num ers side by side, and to arrange only few in series. Moreover, for reasons of economy, the design should be as simple as possible to thereby cheapen the manufacture and operation.

In the annexed drawings, wherein are illustrated different my invention:

Fig. 1 is a side elevation of one form of my invention; Fig. 2 is a cross-sectionon the line 22 of Fig. 1; Fig. 3 is a side elevation of another form of my invention; Fig. 4: is'a cross-section on the line H of Fig. 3; Fig. 5 is a side elevation. of another form of my invention; F ig. 6 is a cross-section on the line 6-6 of Fig. 5; Fig. 7 is a side elevation'of still another form of my invention; and, Fig. 8 is a cross-section on theline 88 of Fig. 7. As shown in the drawing, the evaporator practical embodiments of comprises a plurality of pipes 1, 2, 3, 4, 5, 6,-

which are substantially horizontally arranged in superposed relation, are turned back on themselves in substantially U-shape manner and at one end areupwardly bent perpendicularly, or nearly perpendicularly.

At the other end, the horizontal pipes-terminate in a vertical head 7 which acts as a collecting chamber and separator and in which a predetermined liquid level is maintained so that all the pipes are charged with the liquid. The upwardly bent ends of the pipes terminate in a head or collecting chamber 8, in-which the wet vapors are collected. Chamber 8 communicates with chamber 7 so that the liquid contained in the vapors is separated and quickly returned to the liquid in the head The advantages of the good heat transmission on the one side, according to the physical laws referred to, are fully obtained only if also onjthe other side the heat transmission is good, that is in the present case, on the side of'the heat delivering medium, i. e. the brine. As this depends, to a large degree, on the speed with which the brine passes the pipes andgthe speed in turn depends on the amount circulating per time unit and on the cross-sectional area between the pipes available for the flow, it is evident that it is necessary to make said cross-sectional area as small as possible. To this end, the return of the pipes bent in U-shape can be made ina special manner such, for instance, as shown in Fig. 4, which shows an ogival design, or as shown in Fig. 6 showing one pipe coil nested within a larger pipe coil. The advantages of such an arrangement are more especially evident, if a plurality of vaporizing units are built side by side, which is frequently the case.

Where economy in space is required, the U-shaped coils can be arranged in nested relation, that is, one within the other as shown in Figs. 5 to 8, in which case the inner coils can be given an ogival shape, such as shown in Fig. 8 and the outer coils a circular shape.

In the drawing, the arrows marked a indicate the flow of the refrigerating agent while the arrows marked 6 indicate the flow of the brine. i

I claim:

1. Vaporizer for refrigerating machines comprising a vertical head for the liquid refrigerating agent, a horizontal head for the vapors and a plurality of superposed substantially horizontally'disposed pipes arranged in U-shaped coils bent upwardly at one end, the horizontally disposed ends of said coils terminating in said vertical head and the upwardly bent ends terminating in said horizontal head.

2. Vaporizer for refrigerating machines comprising a vertical head for the liquid refrigerating agent, a horizontal head for the Vapors, a plurality of superposed substantially horizontally disposed pipes arranged in U-shaped coils bent upwardly at one end, the horizontally disposed ends of said coils terminating in said vertical head and the upwardly bent ends terminating in said horizontal head, and a communication between said vertical and horizontal heads.

3. Vaporizer for refrigerating machines comprising a plurality of superposed sub stantially horizontally disposed pipes arranged in U-shaped coils bent upwardly at one end, a header for connecting the ends of said pipes, the upwardly bent ends permitting the discharge of the vapors and the horizontally disposed ends admitting the liquid refrigerating agent, the return portions of said pipes having ogival shape to permit a close juxtaposition of the pipe elements.

4. The combination as specified in claim 3, including a vertical head for the liquid refrigerating agent and a horizontal head for the vapors, the horizontal ends of the pipes terminating in said vertical head and the upwardly bent ends of the pipes termimating in the said horizontal head.

5. The combination as specified in claim 3, including a vertical head for the liquid refrigerating agent and a horizontal head for the vapors, the horizontal ends of the pipes terminating in said'vertical head and the upwardly bent ends of the pipes terminating in the said horizontal head, and a communication between said vertical and horizontal heads for the return of the liquid separated from the vapors to said vertical head.

6. Vaporizer for refrigerating machines comprising a plurality of superposed substantially horizontally disposed pipes arranged in U-shaped coils nested one within the other and having u wardly bent ends, a header for connecting the ends of said pipes, the horizontally disposed ends admitting the liquid refrigerating a ent and the said up wardly bent ends permitting the discharge of the vapors.

7. The combination as specified in claim 6, including a vertical head for the liquid refrigerating agent and a horizontal head for the vapors, the horizontally disposed ends of the pipes terminating in said vertical head and the upwardly bent ends terminating in said horizontal head;

8. The combination as specified in claim 6, including a vertical head for the liquid refrigerating agent and a horizontal head for the vapors, the horizontally disposed ends of the pipes terminating in said'vertical head and the upwardly bent ends terminating in said horizontal head, and a communication between said vertical and horizontal heads.

9. Vaporizer for refrigerating machines comprising a plurality of superposed substantially horizontally disposed pipes arranged in U-shaped coils nested one within the other and having upwardly bent ends, a header for connecting the ends of said pipes, the horizontally disposed ends admittin the liquid refrigerating agent and the sai upwardly bent ends permitting the discharge of the vapors, the return elements of said coils being of ogival shape to permit a close juxtaposition of the nested coils.

In testimony whereof I aifix my signature.

ERICH FREUNDLICH. 

